Optimal plant husbandry requires adherence to the art of irrigation with a fair degree of precision. While established plants can tolerate over and under watering to a certain degree, seedlings are not so tolerant. Efficient farming practices demands that seedlings have a relatively high germination rate with very few areas planted being bare due to improper planting techniques. Uneven terrain coupled with improper irrigation will cause gaps in the produce being germinated from seed, and improper watering seedlings will have a deleterious effect in achieving a proper germination rate.
Extremely small seeds, such as carrot seeds, have a very poor germination rate using conventional irrigation techniques. The primary problem involves controlling the amount of irrigation liquid (e.g., water) and its effect on the seedling when exposed on a surface for germination. Because very small seedlings are unduly influenced by heavy water disposition, small seedlings will fail to stay in a designated spot and instead wash away with the irrigation water into low-lying areas, thereby increasing the seedling density in one area to the exclusion of other areas. Crowded seedlings insure small sized crops unless thinned, requiring manual labor. Even though the art of broadcasting small seedlings in a uniform density is a fairly well-established practice, the art of retaining small seedlings in the spots to which they had been broadcast is difficult when the required subsequent irrigation causes seeds to run-off.
In conventional irrigation systems, a vertical pipe communicates with a horizontal span emanating radially from the vertical pipe and adapted to rotate in a circle about the vertical pipe. By having the horizontal span rotate in a 360-degree arch, one revolution of the span results in a complete irrigation of the underlying area contained beneath the span. A horizontal span as described extends radially outward from the vertical pipe several hundred feet. As a consequence, one complete rotation of the horizontal span can take a considerable amount of time such that successive passes over the same area will not occur frequently enough for small seedlings. Thus, the farmer is faced with the difficult choice of applying a relatively fine mist of water to the delicate seedlings on an intermittent basis and hope for a high germination rate. It bears recalling that soil can only absorb the irrigation liquid at a certain rate, so the farmer is limited with respect to the amount of water that can be dispensed on a single pass versus the amount of time that successive passes can occur on a single span system. Thus, the dilemma heretofore faced by the farmer, is the delicate balancing of spray rate per single pass of a single span versus the absorption of the underlying soil and the seedling size to retain the seed in the desired location and also not wash of soil or other matter cover up the seedlings.
The following patents reflect the state of the art in which Applicant is aware and are included to discharge Applicants acknowledged duty to disclose prior art. It is stipulated that none of the patents teach singlely nor render obvious when considered at any conceivable, permissible combination the nexus of the instant invention as set forth in greater detail herein below.
U.S. Pat. No. 3,647,139 (De Long, Jr., et al.) issued Mar. 7, 1972 to DeLong Jr. et al, provides a rotating tower or turret irrigating or liquid dispensing apparatus which has opposed, horizontally extending, side arm assemblies made up of a plurality of coupled-together liquid-carrying pipe or conduit members that are carried on a central column or mast and provided with sprinkling means or spray heads for rotatably covering a large ground area from a fixed central axis. Each conduit or pipe member is suspended adjacent its opposite ends by cord members that are connected to a column-mounted spread bracket, and is tension-stressed in its positioning along its length between the suspending cord members. This device has four arms 90 degrees apart which are all suspended from a tall center tower and all the arms are driven by a centrally positioned drive wheel.
U.S. Pat. No. 3,902,668 (Daugherty, et al) issued Sep. 2, 1975 to Daugherty, is for a modified center pivot irrigation system for providing a means of irrigating closer to the edges of a square field. The system is modified by adding a secondary boom extension to the end of the distal span of the main boom. The boom is guided along a path defined by an electrical conductor.
U.S. Pat. No. 4,721,061 (McNatt), issued Jan. 26, 1988 to McNatt, shows an apparatus for grazing management and irrigation of a field. A labyrinthine path for animals is defined in the pasture and a movable radially-extending arm carrying an electric fence causes the animals to traverse the labyrinthine path at a very slow rate, e.g. once every two weeks. The arm comprises structure for irrigating the pasture by a gentle drip feed method whereby efficiency in use of both water and land is obtained. A T-joint is pivotally mounted on top of the center post so the two arms are always aligned 180 degrees apart.
U.S. Pat. No. 5,572,954 (Elkins), issued Nov. 12, 1996 to Elkins, provides two center-pivot irrigation systems utilized for controlling grazing. A preceding and succeeding center-pivot system contain electrified fences for containing herds and controlling the extent of their grazing. The preceding system contains water tanks for the herd and the succeeding system irrigates the pasture. together the systems eliminate overgrazing and improve the quality of the herd. There is a ball and socket joint connection between the two arms which only allows 180 degrees of separation between the arms.
U.S. Pat. No. 6,726,132 (Malsam) issued Apr. 27, 2004 to Malsam, claims a corner irrigation system, which includes an ultra wide band (UWB) guidance system. The self-propelled irrigation machine includes an elongated main boom pivoted at one end to a center pivot and supported on a plurality of self-propelled, non-steerable drive units. An extension boom is pivotally secured to the other end of the main boom for irrigating corner areas of the field. A steerable drive tower supports the extension boom and includes a pair of steerable rive wheels. The guidance and control for the extension boom includes a UWB receiver and a computer positioned on the steerable drive tower for receiving and processing UWB information as to the location of the steerable drive tower and for determining the optimal steer angle for the steerable drive wheels relative to the movement of the main boom. At least one UWB transmitters are located within receiving range of the UWB receiver. Signals transmitted by the UWB transmitters are received by the UWB receiver on the steerable drive unit and are used to determine current location and optimal steer angle relative to the main boom.
U.S. Patent Application No. 20040093912, published May 20, 2004 by Krieger, is for an irrigation system for conveying a fluid to a region. The irrigation system comprises a main irrigation portion having an end irrigator span. A corner irrigator span extends radially from the end irrigator span. A control system controls movement of the corner irrigator span. The control system includes a linear movement control system to control a corner drive unit of the corner irrigator span and a steering control system, which controls a steering unit of the corner irrigator span. The steering control system includes a controller that receives control signals from four electrical generators to control the steering unit such that the corner irrigator span follows along an outer boundary of the region. At least one of the electrical generators is an electronic compass for sensing a reference signal to determine a primary control position of the main irrigation portion.